Biometric identification is becoming a popular method for access control and for monitoring secure areas, such as airports. In such settings, it is sometimes necessary to compare the image of a person (or some part thereof) to a previously captured “enrollment” image. Several techniques for biometric identification require certain landmarks to be located and their orientations to be estimated automatically.
Much of the past work on biometrics has considered traditional images, namely integrated light in of the visible part of the electromagnetic spectrum. With the increasing availability and decreasing cost of 3D capture devices, however, there is increasing emphasis on biometric identification from the resulting 3D range (i.e., depth) images.